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  <title>Document</title>
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  <script>
    let arr = [1, 2, 3, [4, 5, [6, 7], 8], 9, [10, 11]]

    function convert(arr){
      let result = []
      arr.forEach(item => {
        if(typeof item === 'number'){
          result.push({
            value: item
          })
        }else if (Array.isArray(item)) {
          result.push({
            children: convert(item)
          })
        }
      })
      return result
    }

    let res = {children: convert(arr)}
    console.log(res)
  </script>
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